精准培育的理念已经渗入到森林培育的各个环节.切根作为干扰根系最为重要的技术,也受到越来越多地重视.切根可以划分为芽苗切根、苗期切根和起苗后切根等3种类型,把平截、扭根、侧方修根、盒式修根等称为苗期切根,是狭义切根范畴.结合苗木形态指标、生理指标和造林效果,综述每一类型的切根对苗木质量和造林效果的影响.以辐射松为代表的主根发达树种,通过芽苗切根、苗期的平截和扭根,抑制根系顶端优势,从而降低苗木高生长,促进侧根发育,形成发达、紧凑的根系,调整苗木地上和地下比例,最终提高苗木造林效果.以花旗松为代表的慢生常绿树种,侧根较为发达,切根效果不一.苗木平截和扭根后,内源激素、矿质营养、碳水化合物、水分等均会发生变化,这种变化如何影响苗木质量的机制尚不明确.%As technologies become more precise to deal with each aspect on silviculture, great attention has been putting on the root pruning which is viewed as the most important root culturing. In this paper, root pruning includes bud-seedling root pruning, post-seedling root pruning, and table pruning. Post-seedling root pruning is divided into undercutting, wrenching, lateral pruning and box pruning. For each type, effects of root pruning on the morphological attributes, physiological attributes and field performance was reviewed. When Pinus radiata, characterized by a carrot - like taproot tree species, is severed by bud-seedling root pruning, undercutting and wrenching, a loss in apical dominance in the entire root system was caused. Following that shoot growth is arrested, lateral root growth increases, a more compact and fibrous root system develops, and shoot-root ratio decreases. These are attributed to the field performance especially in the arid areas. Slower growing evergreen species such as Pseudotsuga menziesii tend to have a more fibrous root system than P. Radiata. Results from root cutting of the species have been more variable. Although hormones, mineral nutrition, carbohydrate, water in the seedlings were responded to root pruning, mechanism of seedling quality regulated by root pruning was inconsistent.
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